But the former Army Ranger decided to walk out of the locker room and stand in the tunnel with his hand over his chest during the rendition. Steelers coach Mike Tomlin stood on his team's sideline during the song, without his team behind him.

The Pittsburgh Steelers empty sidelines are seen during the national anthem before the NFL game against the Chicago Bears Sunday at Soldier Field in Chicago, Ill. Photo by Kamil Krzaczynski/UPI

A spokesman for Fanatics told ESPN that Villanueva has been the most popular player in the NFL, when it comes to merchandise sales on the site, for the last 24 hours.

Tomlin revealed that his team would not participate in the national anthem on the field in an interview before the game.

"We're not participating in the anthem today," Tomlin told CBS. "Not to be disrespectful to the anthem, to remove ourselves from the circumstance. People shouldn't have to choose. If a guy wants to go about his normal business and participate in the anthem, he shouldn't be forced to choose sides. If a guy feels the need to do something, he shouldn't be separated from his teammate who chooses not to. So we're not participating today. That's our decision. We're gonna be 100 percent. We came here to play a football game. That's our intentions, and we're gonna play and play to win."

Steelers defensive end Cam Heyward told ESPN that he supported his teammate's decision.

"I don't want to go into that, but we support our guy Al," he said. "He feels he had to do it. This guy served our country, and we thank him for it."

Pittsburgh players met to discuss a players-only meeting on Saturday at the JW Marriott in Chicago, according to PennLive.com.

Quarterback Ben Roethlisberger introduced three choices of what the team would do before they took a vote, according to the report. The choices were: standing on the sideline holding hands, staying off the field or taking the sideline while some players knelt, others stood and others put their hands on shoulders of kneeling teammates.

Villanueva spoke about Kaepernick and the national anthem with reporters last summer.

"This is the best country in the world," Villanueva said, according to Steelers.com. "If you go to another country, as a minority, I can tell you that there isn't a country with minorities in the world that handles the issues that we have in our country like we do. Everybody has a voice. Everybody has a platform. I don't think we are perfect by any means. Just a couple of days ago, there was a service member killed in Afghanistan. It's one of those things -- there are people that are fighting just so you can say and do whatever you please.

"I agree that America is not perfect. I agree that there are a lot of issues with minorities in this country. And I agree that we should do something about it. But I don't know if the most effective way is to sit down when the national anthem of a country that has provided you freedom and is providing you $60 million a year is the best way to do it, when there are black minorities that are dying in Iraq and Afghanistan that are protecting our freedom for less than $20,000 a year. So, it's his decision. Obviously, he has brought up the issue in a great way, but I think if he encourages other players or other people in the stands to sit down, it's going to send the wrong message. And I think he has to be a little more careful and look at the big picture of the things that he is doing, because as a service member, I have to understand it. I have to understand that. But he's an athlete. He has a huge platform. He has to see the impact that he has on a lot of people's lives. I don't think it's the most effective way."

ICYMI: The Steelers remained inside during the national anthem, but LT and army vet Alejandro Villanueva stood alone outside of the tunnel. pic.twitter.com/rhNVqnHVJz

"If I were to make a statement right now that would affect the amount of money the NFL makes, if I were to go to a company like Pfizer, and I voice my opinion that marijuana should be legalized because it's a much better cure than all the other pharmaceuticals the company sells, and I am affecting the sales of Pfizer, therefore the company should have the right to terminate my contract...to impede this loss of money," he told the Washington Post. "I don't know if it's because of that. If it's simply because of the ideological stand on violence and whatnot, then I think it's very unfair. I think that's the concern all the players have in the NFL. I don't think it should be like that.

"But I don't have all the answers to all the questions. I don't even know how he plays as a quarterback. I don't even know what system fits him. Again, I think he was very brave for taking the chance and doing something, frankly, not a lot of people would have dared to do. I don't know if it was effective or not. I don't know if the fact he was kneeling down was a bigger issue, and people got focused on that and not the fact he was trying to raise awareness. In my opinion, I have an African-American coach, and 90 percent of the team is African American. So I hear these issues nonstop. I don't have to have somebody kneel down for the national anthem. But if somebody, maybe you learn something from them, then I guess it is justified."

The Steelers lost the game 23-17 to the previously winless Chicago Bears.

Villanueva signed a four-year contract with the Steelers in July. The Army graduate joined the team's practice squad in 2014.

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